Coastal Waters

The coastline and the sea have always been at the heart of the attraction of Sussex. The quality of coastal and estuarine waters is fundamental to the economic and social value of fisheries and tourism, as well as marine habitats and wildlife. However, the same geographic area needs to accommodate the development needs of harbour transport, commercial fishing activities and local communities.

The natural coastal environments have no doubt shaped, and been shaped by, the evolution of coastal communities. This will continue to happen, but needs to happen in a joined up way that ensures development and commercial activities benefit from the natural environment, without natural processes deteriorating. In this way, our iconic coastline will remain vibrant and alive.


The catchment supports a large and diverse population of migratory and freshwater fish, which are fundamental to river and marine health, and provide for recreational and commercial fishing. Freshwater angling is supported by a small number of long established local clubs, several of which were founded over 100 years ago. Our estuaries offer popular recreational fisheries and our valuable sea sustains a viable and important commercial fisheries enterprise. 

Much of our main rivers remain fundamentally modified by development during the late 18th and early 19th Centuries, when river channels were dredged and straightened, and many locks and weirs constructed. In-channel structures range from mill construction and dams with medieval origins, to modern gauging weirs, automatic sluices and tidal flaps. Whilst some are essential for flood risk management, water supply and heritage value (such as navigation and milling), many present partial or complete obstacles to fish movement. Implementing improvements to enable fish to navigate barriers, and improve water quality and quantity, are desirable for flourishing fish populations throughout the catchment, which will bring about ecological, and wider social and economic benefits.


The Brighton Chalk Block is the largest aquifer underlying our catchment, visible from the scarp slope springs at Poynings and Fulking to the groundwater fed brooks at Lewes and Offham. It is a crucial water source for public water supply for Lewes, Brighton and Hove, and neighbouring towns on the south coast as well as many rural communities.

The Brighton Chalk Block is vulnerable to abstraction for public water supply, reducing the quantity of water available. Groundwater quality is also at risk from diffuse rural and urban pollution, which contaminate the water with nutrients and pesticides, oils and solvents. Consequently there is a need to reverse increasing trends of pollutants in groundwater across the whole catchment area. A progressive collaborative approach to protected local groundwaters will allow catchment communities to benefit from a truly sustainable ‘ecosystem service’ of naturally occurring high quality drinking water provided by the Brighton Chalk of the South Downs.

Natural Rivers

The Sussex landscape has been significantly changed over the centuries, which has reduced or removed the natural processes and functionality of our rivers. For example, canalisation, culverting and banking to drain land for agriculture, has compromised aquatic habitats and fauna, and water quality.  In addition to the loss of naturalness to our rivers, there has been a dramatic loss of wetland habitat in Sussex over the last 200 years, with over 25% of this loss happening since the 1960s. Reedbed, fen, ancient floodplain woodland and species-rich floodplain grazing marshes are under threat. There is currently no true ecological network in the catchment, although research tells us that the potential for such a network is high.

Our aspiration for natural rivers is not to go back in time, but a direction of travel towards river systems whose geomorphology and habitats can help rebuild ecological networks. This will improve biodiversity, landscape, fish stocks, flood risk and water turbidity, which will in turn maintain the natural capital our commnities and businesses reply on. Improvement must of course be designed to work with local land uses, particularly agriculture, development and heritage.

Water Quality

The quality of waters in our rivers is compromised by a range of pressures, from isolated pollution events to the combined effects of multiple diffuse sources, both rural and urban. Other pressures in quality include increased demand for drinking water, a growing population, the need to increase food production and climate change. Work has been ongoing for many years and must continue, in a number of areas.  Specifically, water company improvements to their infrastructure, best practice land management, and engaging with the wider public on issues such as water demand, domestic pollutants and the general value of surface water quality.

Attempting to tackle these water quality issues across such a wide catchment area will require unique and pioneering solutions. This is a challenge which cannot be completed by one organisation alone – working collaboratively is the only way to protect and improve our water quality.

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